The Hostage of Zir

Blurb

The Hostage of Zir is a science fiction novel written by L. Sprague de Camp, the seventh book of his Viagens Interplanetarias series and the fifth of its subseries of stories set on the fictional planet Krishna. Chronologically it is the third Krishna novel. It was first published in hardcover by Berkley/Putnam in 1977, and in paperback by Berkley Books in 1978. A new paperback edition was published by Ace Books in 1982 as part of the standard edition of the Krishna novels. An E-book edition was published by Gollancz's SF Gateway imprint on September 29, 2011 as part of a general release of de Camp's works in electronic form.
The Hostage of Zir was de Camp's first Krishna novel in a quarter century, the previous one having been written in 1952 and published in 1958.
As with all of the "Krishna" novels, the title of The Hostage of Zir has a "Z" in it, a practice de Camp claimed to have devised to keep track of them. Short stories in the series do not follow the practice, nor do Viagens Interplanetarias works not set on Krishna.